1. Field of the Invention
The present invention relates generally to data transmission, and in particular, to a method, apparatus, and article of manufacture for a reconfigurable notched spectrum for wireless data transmissions.
2. Description of the Related Art
Mobile telecommunications devices have become commonplace. Currently, wireless devices, e.g., cellular telephones, Personal Data Assistants (PDAs), and other devices are sending voice, pictures, video, and other data using Radio Frequency (RF) transmission and reception in cellular telephone systems.
Recently, many cellular providers have begun delivering video clips and other video delivery to cellular telephones and other handheld devices for viewing by a subscriber using higher speed data communications systems. Such delivery requires a large amount of bandwidth of dedicated spectrum for cellular telephones, typically in the 850 MHz or 1900 MHz range of cellular and PCS frequency bands.
Other types of high speed broadband RF transmission systems are possible, such as satellite transmission of voice, data, and video, however, the mobile devices used in such systems are typically much larger than desired because of the additional distance that transmissions from the mobile device are required to travel. The additional distance requires the mobile device to have a larger transmitter power, larger antenna, and, as such, are not quite as desirable to many users.
Further, wireless device users want to be able to use the portable and mobile devices anywhere, including inside of buildings. As such, the systems that support such devices must have a high enough signal strength to penetrate buildings and other structures so that users can operate their mobile devices over a large geographic area without worrying about any interruption of service.
Another typical problem for competing mobile devices is spectrum allocation. The RF frequencies available for transmission are extremely limited, because there are other competing governmental and private entities that have licenses to the frequency spectrum. Further, large contiguous portions of spectrum that would support broadband wireless services are not commonly available for many frequency bands. Only small portions of previously-allocated frequency bands are available, since those portions may not be currently in use by the spectrum owners. Typically, such a small portion is of no use to others, since the portion is not enough to support an entire broadband communications system.
It can be seen, then, that there is a need in the art for portable handheld and mobile devices that can receive broadband data. It can also be seen that there is a need in the art for a mobile device that can be used in a large number of places, including inside buildings, with minimal service interruption. It can also be seen that there is a need in the art for a communications system that can transmit and receive by aggregating smaller parts of the frequency spectrum into a single larger communications channel for use in a broadband service. Such a system can be used to provide fixed broadband service while at the same time providing next generation broadband access for portable and mobile wireless users.